I have
emetophobia.If I get a bad stomach ache I start shaking violently and sweating like crazy in fear of vomiting, my skin goes cold and numb like I was suddenly dropped into cold water.
Same thing happens if someone around me vomits or if I even hear the sound of someone vomiting from another room.
I remember when I was at a band practice a while back and our bassist started throwing chunks after he ate like 8 Slim Jims (He threw up about 5 times in little under an hour).
We practiced at our friend's house in the shed in his backyard, as soon as he started vomiting (He was like 10 feet away from me) I had to run away, I almost fell a few times because I was shaking so hard and I felt really weak. I sat out front crying and shaking as he continued to puke all over the place out back, it took me a while to regain my composure. My friends were surprisingly supportive though (They were also afraid of me after an incident at a bonfire we had, different story, but meh).